Grinding device



Dec. 14 1926.

M. c. HUTTO summum DEVICE Filed sept. 1o. 192s Patented Dec. 14, 1926.

PATENT OFFICE.

MAnsDEN c. nUTTo, or BRYAN, oHIo.

eamnme DEVICE.

Application led September 10, 1923. .Serial No. 661,883.

This invention relates to lapping or grinding devices adapted for the grinding or finishing of substantially cylindrical apertures, and the object of the invention is to provide a device for the purpose stated hav-- ing a plurality of abrading members that are radially adjustable for operation on cylinders of different diameters within the capacity of the device and in which a-control element is utilized to fix the general limit of contraction in any of the adjusted positions of the, abrasive members and free to move subjectfto the control arising through c011- nection with the abrading members. It has commonly been the practice heretofore lto provide a series of radially adjustable abrading members and a control element to adjust the same but in the majority of instances within my knowledge the abrading members of grinding and lappingv devices are spring projected and. thus may yield to inaccuracies of a cylinderpwall being ground and consequently are not efficient in the truing of the cylinder wall as to straightness and uniformity of diameter from end to end. It is further common practice to provide a positive backing for the blades of the reamers and similar tools but in all such cases the adjusting device is not subject to an automatic control or supported by the blades; in other words, theadjusting means or control device in each tool is fixed in the adjusted position.

This invention seeks to obviate the difficulties arising in such previous structures by the provision of an adjusting or control element for the abrading members that floats as a unit in the adjusted position and p rovides a positive lbacking for the abradlng members in the 4grinding operation and by reason of its tloating relationship permits the abradingmembers to lie at an angle to the axis of the tool to fit a tapered wall with- -in the limit permitted by theconstruction of the device. It is therefore an object of this invention to provide, a tool having a series of abrading members radially adjustable and extending parallel with the axis of the tool and a control element that floats` on the longitudinal axis of the tool due to its being supported in position solely by engagement .with the portions provided therefor on the abrading members, the floating movement being subject to control by the abrading members. It is also an object of this invention to provide, in a tool of the character described, a pair 'of cone members with the small ends in opposed relation and supported as a umt in the adjusted position by reason of engagement of the portions of the abrasive j holders adjacent opposite ends respectivelyr Fig. 3 is an enlarged section taken on line 3 3 of Fig. 2.

Fig. 4 is a section taken on line 4 4 of Fig. 3.

Fig. 5 is a perspective view of one of the retaining springs.l

Fig. 6 is a section through an alternative type of lapping number. i

As shown in Fig. 1 the device comprises a handle l mounted in' a member 2 which is provided with a bifurca'ted lower end 3. A

vblock 4 shown in Fig. 3 is secured in the bifurated end 3 by means of the pin 5 which passes through a larger pin 6 extending through the block. The pin 6 is mounted at its outer ends in a pair of upwardly extending lugs 7 which are formed integrallyl with the head 8 ofthe device. The head 8 of the device is provided with a central longitudinal bore 9 therethrough and the three arcuate lapping members 10 are each provided with a pair of pins 11 molded therein, the embedded ends of the pins being provided `with annular grooves 1 2 so as to be securely held in lthe soft lapping metal which is usually lead or a lead com osition or alloy, the `metal being preferab y sulficiently soft to receive an abrasive. A pair of conical members 13 and 14: are mounted in the central bore'9 and are movable-together or apart by adjustment of the screw 15 as will be readily understood. The head 8 is provided with reamed radial apertures 16 for receiving the pins 11 and the ends of the pins are shaped to it the conical members 13 or 14. The head 8 is provided with three dat faces 17 and a spring 18 is mounted on each flat face17 by means of a screw 19,

the ends of each spring 18..:engaging in the notches 2O provided therefor in the pins 11,

the shape of the spring being shown more may be introduced intoa cylindrical aperture of slightly larger diameter and by turning the screw the conical members 13- and 14 are drawn together which spread the lapping faces apart to contact with the cylinder wall, the outward movement of the pins forcing the springs 18 outwardly as shown and the construction is such that the springs press the ends of the pins to engagement with the respective conical members 13 and 14 at all times. Previous to the lapping operation an abrasive compound may be applied to these ,faces 10. At this time the operator by grasping the handle 1 may-move the device u and down and turn it around in the cylin er to correctly lap the cylinder walls, the handle being connected to the head 8 by a universal joint to allow the device to be easily operated from different angles without wearing the cylinder out of round or applying pressure unevenly. As will be seen 1n Figs. 1 and 3 the lapping faces are provided with a rtures 21 therethrough xto allow a screw river to be inserted for loosening or tightening the screw 19 which holds the spring 18 in place. Each device is provided with several sets of lapping faces, each lapping face being provided with pins 11 the same as those shown in Fig. 3 so that by removing ,the spring 18 lapping faces of different diameters may be secured to the head .and allow the device to be used with cylin- Y ders-of greatly varying diameters.

An alternative form of lapping .member may be used as shown in Fig. 6 comprising a base formed of a metalwhich may be die c ast. A grinding stone 32 and a pair of pins 1ll are positioned in the die and the metal is cast therea-bout to securely embed the stone 32 and pins 11 therein. The stone 32 may also be fixed in a metal shell by. use of lead or other adaptable metal 33 between the stone 32 and the flange 31 of the retaining case which also may be considered as a form suggested by Fig. 6. Due to the rounded faces of the stones bein the stones do not have to be changed for lap'- ping different sized cylinders as is the case with the arcuate lapping members shown in Figs. 3 and 4. The `adjustment of the device is thesame with either type of lapping members as will be readily understood and the lapping device when used with the stone -lap-l device for la ping all cylinders within the adjustment o the mechanism.

It will be evident .from the foregoing description that the controlelement,'namely, the cones and adjusting screw float` as a unit with the cones in an adjustably xed or rigidfref'tion on the longitudinal axis of the tool subject to control by reason of contact of the cones with the respective pins of the abrading members and, due to the general relationship of parts and the usual clearnarrow means maintaining plng members provides a universal lapping ances in the itting of the parts, the cones may assume a position causing the abrasive devices at one end to be moved outwardlyand the abrasive members at the opposite end to be moved inwardly to a like extent. This is due to the-fact that the cones are both of the same taper and thus, to the extent permitted by the construction of the tool, the stones may assume an angle to the axis of the tool to fit a tapered cylinder wall having a taper not greater than the permissible taper of the abrasive members.

Preferably the angle of the cone faces relative to the axis of the tool is small, usually not greater than about fifteen degrees, although it may be varied somewhat without materially affecting the operation of the tool but an essential characteristic of the construction shown is that the control element oats as a unit subject to control of the contacting pins of the lapping members 10 l shown in Fi 3 or of the abrasive holder as shown in ig. 6 as these provide the sole support of the adjusting device or control element in the head.

'Preferably also these cone members are formed with a cylindrical portion which fits the bore 9 of the head and thus `the cone members vare positively supported against lateral movement by pressure exerted thereon by the abrasive members.

Having thus fully described my invention, its utility and mode ofoperation, what I claim and desire to secure by Letters Patent ofthe United States`is 1. In a grinding device, a head having a longitudinal bore, a series of abrasive members carried by the head and movable radiallyrelative thereto, said head having a series of apertures opening to the longitudinal bore, pins on the said abrasive devices extending through the said apertures, cone members having the small ends in opposed spaced relation in the lsaid longitudinal bore, said pins of the abrasive devices engaging the respective cones, yieldable the pins in contact with the cones, the said cones positively determining the limit of contraction of the abrasive devices, and means for varying the distance apart of the cones,

the said cones being freely movable as a unit in their adjusted relation.

2. In a grinding device, a head having a central longitudinal bore, a pair of cones in opposed spaced relation freely slidable in and fitting the bore, abrasive devices having portions engaging the respective cones, means for varying thev distance apart oi the cones which maintains positively that adjustment of the cones which determines the limit of contraction of the abrasive devices, the said cones being freely movable as a unit in the adjusted relation, and spring means for contracting the abrasive devices to maintain the said portions thereof in contact with the cones.

3. In a grinding device, a head having a 'central longitudinal bore, a pair of cones ed on the rod and the other cone slidable thereon whereby turning the rod varies the spacing of the cones, a spring tending to maintain the cones inthe determined spaced relation, said cones, rod and spring being freely movable as a unit in the bore, abrasive devices having portions fitting the respective cones, and spring means for contract-- ing the abrasive devices to maintain the said portions 4in contact with the cones, said cones providing a means positively determining the limit of contraction of the abrasive devices.

. 4. In a grinding tool for operation on members having cylindrical apertures, .the combination of a head, a plurality of abrading members having abrading surfaces and radially adjustable in said head, and a. control element having parts adjustably rigid relative to each other to positively fix the general limit of contraction of the abrading surfaces` but free when in operation tomove longitudinally of the body in either direction as a unit subject to control by the abrading members.

5. In a grinding tool for use on members having cylindrical apertures, thev combination of a head, one or m'ore abrading members having abrading surfaces and radially movable in respect to said head, and a control element cooperating with said abrading members and having parts adjustably rigid relative to each other to positively x the general limit 4of contraction of the abrading surfaces, said control element arranged however to automatically allow and control a limited tilting vmovement of the abrading members end for end in setting the abrading members up against cylinder walls nonparallel to the axis of the tool.

6. In a grinding tool for use on members having cylindrical apertures, the combination of a head, one or more abrading members having abrading surfaces and radially guided, and a control element cooperating 'with "said abrading members and having parts adjustably rigid relative to each other A to positively ix the general limit of contraction, said control element arrangedhowever to automatically allow and control a limited tilting of the abrading members end for end in setting the abrading members up `against 1 cylinder walls non-parallel-to the axis of the tool, and to allow and cause the abrading member to automatically assume a parallel position as the cylinder walls are ground toward a parallel condition with respect tov the axis of the tool.

7. In a device for grindin cylindrical apertures, a head, a series of a rasive members extending longitudinally thereof, adjusting means common to said members, adjustableat will and adapted to act through opposite ends thereof to cause the abrasive Y members to engage a surface under presi'A sure, at an angle to the axis of the tool, said means being then still self-adjusting to cause the faces of the abrasive members to gradually assume a position parallel with the axis of the tool as pressure becomes released, said adjusting means providing a positive backing for the abrasive members in any of the operative adjusted or self-adjusted'positions until they are freed by the grinding operation.

8. In a lapping device, a head having a longitudinal bore, a series of abrading members carried by the head and `radially movable therein, cone members having the small ends thereof in opposed relation slidable in the said bore, means for varying the distance apart of the cone members, and maintaining the same relatively rigid, said abrading members each having partsrconnected therewith and engaging the respective cones and providing the sole means of support of the cone members in the bore.

9. In a grinding device, .a head having a central longitudinal bore, a Apair of cones in opposed spaced relation in the said bore, means for varying the distance apart of the cones, and maintainin the same relatively rigid, a series of abrading devices extending longitudinally of the head each provided with means adjacent each end thereof engaging the respective cones whereby the varying of the distance apart of the cones varies the distance of the faces of the abradl ingdevices from the axis of the said bore,

and yieldable means tending to maintain the abrading devices with the said parts in engagement With the respective conesl the said cones being movable as a unit in the ad- -'justed relation in the said bore subject to control b the abrading members.

4 In testimony whereof, I sign this specification. f

MARSDEN .0. HUTTO. 

